Due to the rapid advances in computers, CCD technology, image-processing hardware and software, printer, and copiers, there is an increase potential of fraud by reproducing the patterns and pictures used to verify the authenticity of the objects. The application of optical processing and pattern recognition for security verification of credit cards, passports and other forms of biometric image identification have been proposed (B. Javidi and J. L. Horner, “Optical Pattern Recognition for Validation and Security Verification,” Opt. Eng., 33(6), 1752-1756 (1994); H.-Y. Li, Y. Qiao, and D. Psaltis, “Optical Network for Real-time Face Recognition”, Appl. Opt. 32, 5026-5035 (1993); T. Grycewicz, and B. Javidi, “Experimental Comparison of Binary Joint Transform Correlators Used for Fingerprint Identification,” Opt. Eng., 35(9), 2519-2525 (1996); P. K. H. Fielding, J. L. Horner and C. K. Makekau, “Optical Fingerprint Identification by Binary Joint Transform Correlation,” Opt. Eng., 30(12), 1958-1961 (1991); C. L. Wilson, C. I. Watson, E. G. Pack, “Combined Optical and Neural Network Fingerprint Matching” in Optical Pattern Recognition VIII, D. P. Casasent and T. Chao, ed., Proc. Soc. Photo-Opt. Instrum. Eng. 373-383 (1997); J. Rodolfo, H. Rajbenbach and J-P. Huignard, “Performance of a Photorefractive Joint Transform Correlator for Fingerprint Identification,” Opt. Eng., 34(4), 1166-1171 (1995); Refregier and B. Javidi, “Optical Image Encryption using Input and Fourier Plane Random Phase Encoding,” Opt. Lett., 20, 767-769, (1995); M. Kowalczyk, “Spectral and Imaging Properties of Uniform Diffusers”, JOSA A, Vol. 1, No. 2, 192-200, February 1984; H. Kogelnik and K. S. Pennington, “Holographic Imaging Through a Random Medium”, Optical Society of America., 58, 2, 273-274, (1968) which are incorporated herein by reference).
Various kinds of optical data processing technology for information security have been proposed. (H.-Y. S. Li, Y. Qiao, and D. Psaltis, Appl. Opt. 32, 5026 (1993); B. Javidi and J. L. Horner, Opt. Eng. 33, 1752 (1994); P. Refregier and B. Javidi, Opt. Lett. 20, 767 (1995); F. Goudail, F. Bollaro, B. Javidi, and P. Refregier, J. Opt. Soc. Am. A15, 2629 (1998); C. L. Wilson, C. I. Watson, and E. G. Paek, Proc. SPIE 3078, 373 (1997); D. Weber and J. Trolinger, Opt. Eng. 38, 62 (1999); O. Matoba and B. Javidi, Opt. Lett. 24, 762 (1999), all of which are incorporated herein by reference). In one approach (P. Refregier and B. Javidi, Opt. Lett. 20, 767 (1995), which is incorporated herein by reference), the data are encrypted optically by double-random phase encoding with uniformly distributed random phase keys in both the input and Fourier planes. In addition, digital holographic techniques (U. Schnars and W. Juptner, Appl. Opt. 33, 179 (1994); B. W. Schilling, et al, Opt. Lett. 22, 1506 (1997); E. Cuche, F. Bevilacqus, and C. Depeursinge, Opt. Lett. 24, 291 (1999), which are incorporated herein by reference) that use a CCD camera for direct recording of a hologram have become available owing to the development of the imaging technology.
The following references are incorporated herein by reference in their entirety: R. O. Duda, P. E. Hart, Pattern Classification and Scene Analysis, J. Wiley and Sons, 1973; R. Schalkoff, Pattern Recognition Statistical, Structural and Neural Approaches, J. Wiley and Sons 1992; P. Hariharan, Optical Holography Principles Techniques and Approaches, Cambridge University Press 1984; W. H. Lee, Computer Generated Holography, Techniques and Applications, Progress in Optics, Vol. 16, Ed., E. Wolf, Amsterdam North Holland 1978; J. W. Goodman, Introduction to Fourier Optics, McGraw-Hill 1996.